Yep, someone is collecting stinkpipes: "Our mission is to find, map, photograph and catalogue every stinkpipe in the Greater London area, though out of London is welcome too. Please send your stinkpipe pics." Power to you.

"A site dedicated to those rather odd looking pavement objects you find in the most interesting of places..... Bollards have a history richer than most objects placed upon the pavement and we can easily find some dating back to the earlier part of the 19th Century."